automatic lampenwechsler and lampendrehkopf to holders of several lamps

摘要

1,128,770. Lamp changers. WALLACE & TIERNAN Inc. 15 June, 1967 [16 June, 1966], No. 27613/67. Heading F4R. [Also in Division H2] An automatic lamp changer comprises a rotary turret 24 adapted to carry a number of lamps L, a driving mechanism which rotates the turret in response to the failure of the lamp in the operative position so as to bring another lamp into the operative position, and a housing comprising a pair of releasably interconnected sections 30, 32 having opposed plane face plates 26, 28 between which the turret is mounted, one of the sections enclosing the driving mechanism and the other enclosing the control circuit for the driving mechanism. The turret is a one-piece plastic injection moulding comprising a web 68 and a generally cylindrical flange 70 provided with apertures 72 and slots 74 to receive the lamp bases, the turret being rotatable on a shaft 58 supported in an aperture 50 in the face plate 28. Electrical contact with the lamps is made by a series of resilient fingers 76 connected to studs 78 which engage a lamp contact LC in the operative position, and a spring spider 62 having radial fingers 64 which press against flanges 66 on the lamp bases. The spider 62 serves the additional purposes of urging the turret towards the face plate 28, thereby holding it in position, and connecting it to the driving mechanism which is located in the housing section 30 and comprises a ratchet motor RM coupled to the spider drive shaft 122 by reduction gearing. The ratchet motor control circuit (see Division H2) includes a reed switch S1 the coil of which is in series with the operative lamp, so that if this lamp fails the switch opens and causes a silicon controlled rectifier to become conductive and supply current to the motor. When a good lamp reaches the operative position the rectifier ceases to conduct and the turret stops. A cam-operated switch is provided to prevent further rotation of the turret after the final lamp has reached the operative position. The housing sections are pivotally connected by a pin 56 and are locked in their normal positions by means of resilient levers (48, 50, Figs. 6-8, not shown) which are secured to the section 30 and engage under latch shoulders (52, 54) on the plate 28. Disengagement of the levers from the shoulders enables the sections to pivot apart and the turret to be released.